This global parameter determines if the tdb internals of Samba can depend on mmap working correctly on the running system. Samba requires a coherent mmap/read-write system memory cache. Currently only OpenBSD and HPUX do not have such a coherent cache, and on those platforms this parameter is overridden internally to be effectively no. On all systems this parameter should be left alone. This parameter is provided to help the Samba developers track down problems with the tdb internal code. yes